Resiliently yieldable rail fastening

ABSTRACT

A fastening device for fastening to a railway tie a rail comprising at least one resiliently yieldable fastening plate bearing on the flange of the rail and on the tie. The plate is provided with an aperture for the passage of plate-tightening means and has in its centre part, in the region of the aperture, a thickening defining a curved boss for bearing against the tightening means in a contact point located between a region in which the fastening bears against the tie and a region in which the fastening bears against the flange of the rail. The plate is thinned down progressively from the boss in the direction of each of the ends of the plate. The fastening pivots around the contact point as the rail vertically moves. The thickness of the plate however is constant adjacent its ends which form two thin very flexible feet. A boss may also be provided on the lower face of the plate.

United States Patent Duchemin RESILIENTLY YIELDABLE RAIL FASTENING [75]Inventor: Michel Duchemin, Lambres Les Douai, France [73] Assignee:Ressorts du Nord S.A., Paris, France [22] Filed: May 3, 1974 [21] Appl.No.: 466,919

[30] Foreign Application Priority Data May 3, 1973 France n 7315918 [52]U.S. C1. 238/349; 238/283; 238/310 {51] Int. Cl. E0111 9/30 [58] Fieldof Search 238/349, 351, 310, 283

[56] References Cited UNITED STATES PATENTS 2,203,994 6/1940 Magee238/349 2,526,005 10/1950 Carpenter 238/349 3,688,984 9/1972 Sonneville238/349 3,784,098 1/1974 Serafin et al 238/349 June 10, 1975 PrimaryExaminer-M. Henson Wood. Jr.

Assistant Examiner-Richard A. Bertsch Attorney, Agent, or Firm-Burns,Doane, Swecker & Mathis [57] ABSTRACT A fastening device for fasteningto a railway tie a rail comprising at least one resiliently yieldablefastening plate bearing on the flange of the rail and on the tie, Theplate is provided with an aperture for the passage of plate'tighteningmeans and has in its centre part, in the region of the aperture, athickening defining a curved boss for bearing against the tighteningmeans in a contact point located between a region in which the fasteningbears against the tie and a region in which the fastening bears againstthe flange of the rail. The plate is thinned down progressively from theboss in the direction of each of the ends of the plate. The fasteningpivots around the contact point as the rail vertically moves.

The thickness of the plate however is constant adjacent its ends whichform two thin very flexible feet. A boss may also be provided on thelower face of the plate.

12 Claims, 4 Drawing Figures 20 1 f s a 7 2 1 a r I 1 1 PATENTEDJUH 10ms SHEET FIG.2

FIG.5

RESILIENTLY YIELDABLE RAIL FASTENING As the speed of trains isconstantly increasing and as their comfort must always improve. one isled to interpose, between the rail and the sleeper or tie supporting it,an elastically yieldable pad which is becoming thicker and thicker andmore and more flexible, with result that the extent of the verticalmovement of the rail increases which requires the use of increasinglyflexible fastenings for fastening the rail to the sleeper.

Moreover, the fastening must oppose the tipping of the rail under theaction of lateral forces exerted on its head, that is to say, thefastening must be strong enough to preclude any raising of the flange ofthe rail.

For this purpose, rails are generally fastened by means of fastenings inthe form of spring plates or strips which bear, at one end, on theflange of the rail and, at the other end, on the support and areprovided with an aperture for the passage of fastening-tightening means.However, the flexibility of the conventional fastenings is no longersufficient.

An object of the present invention is to provide an extremely flexibleand strong rail fastening device whereby it is possible to maintain arail even when it is mounted on a very flexible pad.

According to the invention, there is provided a fastening devicecomprising at least one resiliently yield able fastening plate bearingon the flange of the rail on the sleeper and provided with an aperturefor the passage of tightening means, the fastening comprising in itscentre part in the region of the aperture a thickening constituting acurved boss for bearing against the tightening means at a point locatedbetween a bearing point or points between the fastening and the sleeperand a bearing point or points between the fastening and the rail flange,the fastening being progressively thinned down from the boss in adirection toward each of its ends.

Preferably, the plate terminates at each end beyond the thinned downpart in a thin foot which has a substantially constant thickness.

Owing to its centre boss, the fastening is pivotable about its point ofcontact with the tightening means. Thus, when the elastically yieldablepad supporting the rail is depressed, it is completely relieved andcontributes in its entirety at the maintenance of the rail. Now, thethinning down of the two parts of the fastening imparts to the branchbearing on the sleeper the same flexibility as the branch bearing on therail, so that the fastening may have maximum flexibility. On the otherhand, when the rail is at rest. the plate abuts against the head of thetightening means not only through its thickest part but also through theneighbouring portions lo cated between the boss and the flange of therail. so that the rail is held completely stationary against any lateraltipping.

Embodiments of the invention will now be described by way of examplewith reference to the accompanying drawings.

In the drawings:

FIG. I is a longitudinal sectional view of a fastening according to theinvention;

FIG. 2 is a plan view of the fastening shown in FIG. 1;

FIG. 3 is a sectional view of a rail fastening device employing thefastening shown in FIG. I;

FIG. 4 is a sectional view of a modification of the device shown in FIG.3;

FIGS. 5 and 6 are sectional views of two other modi fications of therail fastening device according to the invention;

FIG. 7 is a side elevational view of a modification of the fastening.and

FIG. 8 is a plan view of the fastening shown in FIG. 7.

The fastening shown in FIG. 1 comprises a resiliently yieldable metalstrip or plate I provided with a centre aperture 2 for the passage offastening-tightening means. This plate has in the region of the aperture2 a thickening which forms a boss 4 on one of the faces of the plate. Oneach side of this boss, the thickness of the plate decreasesprogressively in the direction of each of its ends. However, thisreduction in thickness stops preferably at 6 and 8 at a distance fromsaid ends so that the plate I terminates in two thin very flexible feet10, I2 of substantially constant thickness so that the fastening has oneach side of the boss 4 two branches ll, 13 which are thinned down in asimilar manner.

The surface 14 of the plate 1 opposite the boss 4 is preferably planar.This surface 14 is rectangular in the embodiment shown in FIG. 2, thefeet I0 and I2 having the same width as the centre part of the plate.But the plate may have any other preferred shape, the feet It) and 12being either wider or narrower than the rest of the plate.

In the fastening device shown in FIG. 3, the plate I bears at one endagainst the flange 16 of a rail [8 whereas at the other end it is incontact. through the foot 12. with the sleeper or tie T which supportsthis rail. A coach-screw 20 extends through the aperture 2 and isscrewed in the sleeper T. A head 22 of this coach-screw exerts a forceon the upper surface of the plate I in the region of the boss 4 andapplies the fas tening against the flange 16 of the rail as shown inFIG. 3 in constraining it to flex and bend.

The c ..ach-screw 20 is sufficiently near to the flange 16 to alow itshead 22 to extend slightly over the flange so that the tightening downof the fastening plate is limited by the contact of the plate 1 with theedge 17 of this flange. In this position, the foot 10 of the fasteningis clamped or tightened against the flange I6 and is in full contacttherewith with a uniformly-distributed pressure. The head 22 bears, asshown in the drawing, not only on the top of the boss 4 but also on theneigh bouring part of the plate I, that is to say, on the thickest partof the branch 11. Thus no raising of the rail I8 is possible. On theother hand, on the other side of the coach-screw 20, a space 24 remainsfree between the head 22 and the branch 13 and the foot 12 is in fullcontact with and exerts a uniformly-distributed pressure on the sleeper.

The rail 18 is mounted on the sleeper T with interposition ofa pad 25composed of a very flexible elastically yieldable material.Consequently, when a train passes over the rail and its weightcompresses the pad 25 and moves the flange l6 nearer to the sleeper T,the branch II of the plate I is untightened and leaves its support underthe head 22 and only the top of the boss 4 remains in contact with thehead. There results a reliev ing of said plate I and a pivoting of thefastening about this single point of contact with the head 22. Thethickening of the boss 4 promotes this pivoting and performs thefunction of an articulation or pivot so that the whole of the plate thatis to say. both branch 13 and branch 11 participates in the flexibility.only the foot 12 remaining rigid. The force exerted by the tighteningmeans remains applied at its point of contact with the plate and thereaction on the rail and on the sleeper are respectively localized inthe regions of the feet and 12.

There is thus provided a fastening which has very high resilience withgreat strength. A fastening of maximum flexibility, which is that inwhich each section has a modulus of inertia proportional to the bendingmoment applied thereto. can be easily constructed. the increase in thethickness in the vicinity of the aperture 2 compensating for thereduction in the useful width.

It will be understood that the circular aperture 2 shown in FIG. 2 maybe replaced. in order to facilitate the assembly. by a longitudinalnotch without modifying in a marked manner the strength of the assembly.It is sufficient to conserve the same shape for the upper face of thebranch 13 which extends over the sleeper.

Moreover. in some cases. it may be preferable to pro vide the lowersurface 14 of the plate 1 also with a boss constituted in the same wayas the boss 4 by a local thickening of the plate in the oppositedireection. The second boss constitutes a bearing point on the sleeper Tand defines a free space between this bearing point and the foot 12 incontct with the sleeper. This lower boss is preferably exactly oppositethe boss 4 and, in the same way as the latter, coaxialwith the aperture2. However. this second boss may be. in the same way as the upper boss.laterally offset from the aperture 2. FIG. 4 shows an embodiment of thistype. It shows a de vice for fastening a rail to a sleeper or tie T, ofconcrete in which the fastening is constituted by a plate or strip 3iwhich has, in the same way as the plate 1, a boss 26 on its upper facein the region of the aperture 32 for the passage of the tightening means30, but this boss is not centred on this aperture but laterally offsetonto the branch 27 of the fastening adapted to bear on the flange 16 ofthe rail. The plate 31 further comprises on its lower face a second boss28 which is also laterally offset from the aperture 32 for the passageof the tightening means but in the direction of the opposite end, thatis to say. on the branch 29 which is adapted to come in contact with thesleeper.

The rail 18 is disposed in a recess 34 in the sleeper T of concrete.bears against a pad 35 and is blocked or retained laterally by means ofblocks 36 which are preferably of an electrically insulating materialand fill the recess 34 on each side of the rail 18 and extends along theupper part of the corresponding flange 16.

The branch 27 of the plate is tightened against this insulating block 36by means of a nut 38 screwed on the bolt 30. The nut 38 is in contactwith the boss 26 and with the neighbouring portion of plate 31. On theother hand. a space 40 remains empty on the other side of the boltbetween the latter and the part of the plate 31 which is locateddirectly above the boss 28. In the same way as in the device shown inFIG. 3. when the flange of the rail compresses the pad 35, the plate 31pivots about the point of Contact of the boss 26 with the nut 38 whichraises the boss 28 off the sleeper and enables the whole of the plate toparticipate in the resilience of the fastening. On the other hand. whenthe device is in the illustrated position. the whole of the platelocated between the boss 28 and the flange l6 constitutes a relativelythick means which is sufficiently rigid 4 to strongly maintain the rainagainst any lateral tipping notwithstanding the fact that the nut 38does not extend over the flange 16.

The fastening plate provided with a thickening at its 5 centre part mayalso be employed for other types of sleepers or ties. In particular. itmay b rnounted on metal sleepers provided with lateral abutments orstops on each side of the position of the rail. such as those shown inFIGS. 5 and 6. in this case. the fastening 41 extends over the abutmentand the tightening bolt 42 extends in succession through the aperture inthe plate and an aperture in the abutment 48. The fastening 41 istherefore not only thinned down but also curved in such manner as toallow the foot 46 at the end of the branch 45 to come in contact withthe sleeper. whereas the foot 44 of the opposite branch 43 bears againstthe flange 16 on the other side of the abutment 48. This fasteningcomprises an upper boss 50 in contact with the tightening bolt andpreferably a lower 52 on the op posite side of the plate and in contactwith the abutment 48. A lateral packing block 54 constituting anelectrically insulating cladding is interposed between the flange 16 ofthe rail, the abutment 48 and the branch 43 of the fastening 44. Thisbranch 43 is tightened against the flange l6 and is in contact with thelatter in the region of the foot 44 and in the region of the edge 17 ofthis flange. However, as the branch 45 is only in contact with thesleeper by the foot 46, the fastening pivots with respect to thetightening means 42 in the same way as the fastenings l and 31 when thepad is compressed.

The lateral abutment 48 may be a projecting portion integral with thesleeper or constituted by an independent member 58 which extends throughan aperture 56 in the sleeper as shown in FIG. 6. The abutment 58 isthen hollow and maintained in position, together with the fastening 41,by the tightening means 42.

It must be understood that the fastening may be constituted by a singleplate or strip or by a plurality of plates or strips in superimposedrelation forming together the thickening constituting the upper bossand. if provided, a lower boss (FIGS. 7 and 8). For example, a fastening60 may comprise a lower plate or strip 62 of constant thickness andadapted to bear against the sleeper adjacent one end of the strip 62 andagainst the flange of the rail adjacent the other end, this lower platebeing associated with a second plate or strip 64 whose thickness variesand is maximum in the centre part at 65. The two plates are'provided inthis centre part with an aperture 66 for the passage of tighteningmeans. The thickness of the second plate 64 decreases progressively fromthe aperture 66 to its ends. However, its length is less than that ofthe plate 62 and the ends of the latter form on each side of the plate64 two thin feet of constant thickness. The width of the plate 64 may bethe same as that of the plate 62 or less and decrease progressively atthe same time as the thickness decreases in the direction of each of theends of the fastening.

Other plates or strips may also be superimposed on the plates 62 and 64or. in some cases. the fastening may have a plurality of plates orstrips whose thicknesses. and possibly widths. are variable. Such anassembly of superimposed plates constitutes. in the same way as a singleplate. a very strong fastening which is nonetheless highly flexible.Preferably. the thickness and the width of the plates are so chosen thateach section has a modulus of inertia which is proportional to thebending moment applied thereto so as to achieve maximum flexibility.

Having now described my invention what I claim as new and desire tosecure by Letters Patent is is:

l. A fastening device for fastening to a railway tie a rail which has aflange and is supported by the tie through an elastically yieldable pad,comprising a fastening comprising at least one resiliently yieldableplate bearing, in a first branch adjacent one end of the fastening at atleast one point of the fastening, against the tie and, in a secondbranch adjacent an opposite end of the fastening at at least one pointof the fastening, against the flange of the rail, means defining in theplate an aperture, between the two branches, the fastening having athickening in a centre part of the fastening in the region of theaperture constituting a curved boss, the fastening progressivelythinning down from the boss in directions toward said ends of thefastening", and tightening means for tightening down the fastening ontothe rail flange extending through the aperture and connected to the tie,the tightening means being pivotally engaged with the upper face of theboss at a contact point located between a region in which the fasteningbears against the tie and a region in which the fastening bears againstthe flange of the rail, whereby said fastening pivots around saidcontact point as the pad is compressed or depressed by the rail.

2. A fastening device as claimed in claim 1, having a constant thicknessin the vicinity of each of said ends so as to constitute a foot adjacenteach end, its thickness decreasing between said boss and said feet.

3. A fastening device as claimed in claim 1, compris ing a plurality ofsuperimposed plates of which at least the uppermost plate has athickening in its centre part.

4. A fastening device as claimed in claim 3, comprising at least oneplate of constant thickness and a plate of variable thickness.

5. A fastening device as claimed in claim 1, wherein the boss has awidth which decreases on each side of the aperture in the directions ofsaid ends.

6. A fastening device for fastening to a railway tie a rail which has aflange and is supported by the tie through an elastically yieldable pad,comprising: a fastening comprising at least one resiliently yieldableplate bearing, in a first branch adjacent one end of the fastening at atleast one point of the fastening, against the tie and, in a secondbranch adjacent an opposite end of the fastening at at least one pointof the fastening, against the flange of the rail, means defining in theplate an aperture between the two branches, the fastening having athickening in a centre part of the fastening in the region of theaperture constituting a curved first boss, the fastening progressivelythinning down from said first boss in directions toward said ends of thefastening; and tightening means for tightening down the fastening ontothe rail flange extending through the aperture and connected to the tie,the tightening means being pivotally engaged with the upper face of saidfirst boss at a contact point located between a region in which thefastening bears against the tie and a region in which the fasteningbears against the flange of the rail and a second boss on the oppositeside of the fastener to the first boss, whereby said fastening pivotsaround said contact point as the pad is compressed or depressed.

7. A fastening device as claimed in claim 6, wherein the two bosses areexactly aligned with each other,

8. A fastening device as claimed in claim 6 wherein the two bosses arelaterally offset with respect to each other and with respect to theaperture, the offsets being respectively in directions toward said ends.

9. A device for fastening to a railway tie a rail which has a flange andis supported by the tie through an elastically yieldable pad,comprising: a fastening comprising at least one resiliently yieldableplate bearing. in a first branch adjacent one end of the fastening at atleast one point of the fastening, against the tie and, in a secondbranch adjacent an opposite end of the fastening at at least one pointof the fastening, against the flange of the rail, means defining in theplate an aperture. the fastening having a thickening in a centre part ofthe fastening in the region of the aperture constituting a curved boss,the fastening progressively thinning down from the boss in directionstoward said ends of the fastening; and tightening means for tighteningdown the fastening onto the rail flange extending through the apertureand connected to the tie, the tightening means being in contact with theboss and with a portion of the second branch of the fastening, therebeing defined between the tightening means and the first branch of thefastening a free space, the end of the fastening corresponding to saidfirst branch being flat on the tie. the boss bearing against thetightening means at a contact point located between a region in whichthe fastening bears against the tie and a region in which the fasteningbears against the flange of the rail.

10. A device as claimed in claim 9, comprising an abutment for limitingthe lateral displacement of the rail relative to the tie and integralwith the tie and located between the rail and the tightening means, anda lateral electrically-insulating rail-blocking packing block interposedbetween a side of the rail and said abutment and covering an upper partof the flange of the rail, the second branch of the fastening bearing onsaid block.

11. A device as claimed in claim 10, wherein the abutment is formed by aside of a projecting portion in one piece with the tie and thetightening means is fixed in said projecting portion.

12. A device as claimed in claim 10, wherein the abutment comprises anattached member which is fixed to the tie by the tightening means. i

1. A fastening device for fastening to a railway tie a rail which has aflange and is supported by the tie through an elastically yieldable pad,comprising : a fastening comprising at least one resiliently yieldableplate bearing, in a first branch adjacent one end of the fastening at atleast one point of the fastening, against the tie and, in a secondbranch adjacent an opposite end of the fastening At at least one pointof the fastening, against the flange of the rail, means defining in theplate an aperture, between the two branches, the fastening having athickening in a centre part of the fastening in the region of theaperture constituting a curved boss, the fastening progressivelythinning down from the boss in directions toward said ends of thefastening; and tightening means for tightening down the fastening ontothe rail flange extending through the aperture and connected to the tie,the tightening means being pivotally engaged with the upper face of theboss at a contact point located between a region in which the fasteningbears against the tie and a region in which the fastening bears againstthe flange of the rail, whereby said fastening pivots around saidcontact point as the pad is compressed or depressed by the rail.
 2. Afastening device as claimed in claim 1, having a constant thickness inthe vicinity of each of said ends so as to constitute a foot adjacenteach end, its thickness decreasing between said boss and said feet.
 3. Afastening device as claimed in claim 1, comprising a plurality ofsuperimposed plates of which at least the uppermost plate has athickening in its centre part.
 4. A fastening device as claimed in claim3, comprising at least one plate of constant thickness and a plate ofvariable thickness.
 5. A fastening device as claimed in claim 1, whereinthe boss has a width which decreases on each side of the aperture in thedirections of said ends.
 6. A fastening device for fastening to arailway tie a rail which has a flange and is supported by the tiethrough an elastically yieldable pad, comprising: a fastening comprisingat least one resiliently yieldable plate bearing, in a first branchadjacent one end of the fastening at at least one point of thefastening, against the tie and, in a second branch adjacent an oppositeend of the fastening at at least one point of the fastening, against theflange of the rail, means defining in the plate an aperture between thetwo branches, the fastening having a thickening in a centre part of thefastening in the region of the aperture constituting a curved firstboss, the fastening progressively thinning down from said first boss indirections toward said ends of the fastening; and tightening means fortightening down the fastening onto the rail flange extending through theaperture and connected to the tie, the tightening means being pivotallyengaged with the upper face of said first boss at a contact pointlocated between a region in which the fastening bears against the tieand a region in which the fastening bears against the flange of the railand a second boss on the opposite side of the fastener to the firstboss, whereby said fastening pivots around said contact point as the padis compressed or depressed.
 7. A fastening device as claimed in claim 6,wherein the two bosses are exactly aligned with each other.
 8. Afastening device as claimed in claim 6 wherein the two bosses arelaterally offset with respect to each other and with respect to theaperture, the offsets being respectively in directions toward said ends.9. A device for fastening to a railway tie a rail which has a flange andis supported by the tie through an elastically yieldable pad,comprising: a fastening comprising at least one resiliently yieldableplate bearing, in a first branch adjacent one end of the fastening at atleast one point of the fastening, against the tie and, in a secondbranch adjacent an opposite end of the fastening at at least one pointof the fastening, against the flange of the rail, means defining in theplate an aperture, the fastening having a thickening in a centre part ofthe fastening in the region of the aperture constituting a curved boss,the fastening progressively thinning down from the boss in directionstoward said ends of the fastening; and tightening means for tighteningdown the fastening onto the rail flange extending through the apertureand conneCted to the tie, the tightening means being in contact with theboss and with a portion of the second branch of the fastening, therebeing defined between the tightening means and the first branch of thefastening a free space, the end of the fastening corresponding to saidfirst branch being flat on the tie, the boss bearing against thetightening means at a contact point located between a region in whichthe fastening bears against the tie and a region in which the fasteningbears against the flange of the rail.
 10. A device as claimed in claim9, comprising an abutment for limiting the lateral displacement of therail relative to the tie and integral with the tie and located betweenthe rail and the tightening means, and a lateral electrically-insulatingrail-blocking packing block interposed between a side of the rail andsaid abutment and covering an upper part of the flange of the rail, thesecond branch of the fastening bearing on said block.
 11. A device asclaimed in claim 10, wherein the abutment is formed by a side of aprojecting portion in one piece with the tie and the tightening means isfixed in said projecting portion.
 12. A device as claimed in claim 10,wherein the abutment comprises an attached member which is fixed to thetie by the tightening means.